The trabecular meshwork in the chamber angle is the major site for the regulation of aqueous outflow. The obstruction of aqueous outflow is generally believed to be the precipitating factor in intraocular pressure elevations and glaucomatous conditions. We propose to study the ultrastructure, and the phagocytic, chemotactic, and synthetic activities of the trabecular meshwork in health and disease. An in vitro system will be established initially. Tissue cultures and organ cultures of trabecular meshwork cells will be derived from (i) normal monkey eyes, (ii) normal human eyes, (iii) eyes from patients with primary open angle glaucoma and secondary glaucomas for morphologic, physiologic, and biochemical investigations. These cells will also be examined after experimental manipulations such as with glycosaminoglycans, and with iron-containing compounds, and with argon laser treatments. Subsequently, three animal systems will be established to assess the in vivo response of trabecular meshwork cells to experimental manipulations. The trabecular meshwork in monkey eyes will be exposed to glycosmainoglycans, and iron, and will be subjected to argon laser trabeculoplasty for morphologic, physiologic, and biochemical effects. In the investigations of the above in vitro and animal in vivo systems, the morphology will be studied by light and electron microscopy combining histochemical and immunochemical techniques. The phagocytic and chemotactic activities of trabecular meshwork cells will be examined by physiologic methods. Biochemically, the synthesis of extracellular matrix materials such as collagen, proteoglycans, fibronectin, and laminin and the lectin-binding sites will be studied. Results from the different systems will be compared.